No drainage?

[MadeUpName]

Hi,

Hoping for some pointers on drainage. I've recently moved into a house at the bottom of a hill. The previous owners had the house extended and the driveway block paved. The land and drive all slope down to the front of the house and connected garage. There are no downpipes at the front of the original house and no obvious drainage, other than naturally soaking into the ground.
There's an ACO drain between the drive and garage, but it goes nowhere, water just sits until it overflows into the gully below it. That is just filled with gravelly soil which soon becomes waterlogged.
The paving outside the front door pools with water and the gully along the front of the house does the same. There's no apparent connection under the block paving between the garage gully (to the left of the front door in the picture) and the gully to the right of the front door. The ground all falls away towards the downpipe on the extension but there's nothing actually connected, no French drain/ buried pipe or anything.

To sum up, there doesn't seem to be any functional system of surface water management at the front of the house. Is it normal to expect the ground to just absorb it or should I be looking at getting a French drain installed and connected to that downpipe?

Thanks for any advice.

 

[ree]

OP,
In the last pic the downpipe discharge arrangement at what should be a custom gully is wrong but presumably cannot be corrected until the remaining drainage is sorted out? Is this the lowest point of the house?
From what I can understand, It appears that you need, at a min. linear drainage (ACO) all around the house & extension.
The linear drainage should be falling from the highest point to the lowest point ie. to the, presumed, discharge point at the new gully arrangement?
But where does the existing rainwater "gully" discharge to? Is there a nearby manhole? Or does it go to a soakaway or simply into the ground?

 

[MadeUpName]

Hi,

The lowest point of the house is in the back garden (opposite side of house to all of the pictures). According to the original plans for the extension the downpipe drain should route under the extension and join the existing drainage system at the back of the house (I'll have to test with a hose at some point).

The custom gully in the pictures is where I've dug up because there was hardly any clearance under the damp course and air bricks. Before that the water just sat and eventually soaked into the ground.

Although, (worryingly?) a lot of it seemed to find a natural flow to that 90 degree corner where the extension meets the original house. The ground seemed extra soft there when digging. Also, the original plans had the downpipe on that corner, but it seems to have moved during the build.

In short, no manhole, no apparent soakaway, water just soaks into the ground.

 

[noseall]

OP,
In the last pic the downpipe discharge arrangement at what should be a custom gully is wrong but presumably cannot be corrected until the remaining drainage is sorted out? Is this the lowest point of the house?
From what I can understand, It appears that you need, at a min. linear drainage (ACO) all around the house & extension.
The linear drainage should be falling from the highest point to the lowest point ie. to the, presumed, discharge point at the new gully arrangement?
But where does the existing rainwater "gully" discharge to? Is there a nearby manhole? Or does it go to a soakaway or simply into the ground?

There is no drainage.

 

[noseall]

In short, no manhole, no apparent soakaway, water just soaks into the ground.

Asses the ground conditions - i.e. do you have permeable ground or is it clay? If permeable, dig a soakaway front or rear or both and drain your surface water into it. If clay, then either seek out a dedicated storm system (if one exists) or ascertain whether the houses were built with a dual system in mind - i.e. look at your water bills and storm handling.

 

[MadeUpName]

Asses the ground conditions - i.e. do you have permeable ground or is it clay? If permeable, dig a soakaway front or rear or both and drain your surface water into it. If clay, then either seek out a dedicated storm system (if one exists) or ascertain whether the houses were built with a dual system in mind - i.e. look at your water bills and storm handling.

Trouble is I don't have an available area that is 5m from both the house and public areas.

Not had a water bill yet due to recently moving, but I'll definitely look at that aspect.

I queried the lack of drainage with the surveyor and they said its acceptable to expect the water to just soak away naturally. Perhaps part of the problem is that the gravelled area has compacted the soil under the weed matting to the point that water runs down to the building before it gets chance to soak into the ground.

 

[ree]

OP,
You mention "the existing drainage system". Do you mean rainwater from the main house gutters? To where?
Where is your soil stack?
Where do the waste pipes from the fixtures (sink, bath etc.) discharge?
The sewage pipe from the soil stack will run to a manhole inside your property line or not far outside it.
Or, do you have a Septic tank or a Cess pit?

Your water utility will often give you permission to link in your rainwater with the main sewage if there's no reasonable alternative.
One way of dealing with ground water coming down hill is to build a couple of terraced retaining walls - but your ground water is coming down your drive, so to speak. Dont divert water on to a neighbour's property.
What have your hillside neighbours done about this problem?
Another possibility would be to contact "pavingexpert.com" or similar sites?

 

[noseall]

Look at his last paragraph - opening post. Pay attention.

 

[MadeUpName]

Hey, no arguing on my post!

Soil stack and 3 manholes are all at the back of the house. From a quick check I did when I first moved in, they all seem to link then discharge into the sewage system.
The existing infrastructure (kerbs, walls,etc.) do divert most of the hillside water, it's the direct rainfall that pools against the house and garage.
Neighbour's houses seem similar - water management taken care of at the back of the house, water at the front just left to soak into the ground.
I should clarify, our houses are not at the very bottom of the hill, behind us is a main road then the hill continues down as a farmers field into a fairly steep valley.
Once through the top layer the ground seems pretty permeable, which makes me wonder if the original design just assumed the water would soak away efficiently due to the valley behind us. I'm just concerned that subsequent work on both the house and the road behind us has made a "shelf" with its own localised water table.

 

[noseall]

The OP's reference was to: "surface water" not to water from the gutter.

Gutter water is surface water.

 

[MadeUpName]

For clarity then:

I've got no problems with the roof rainwater, the existing guttering/pipework seems to handle it fine.

The "channel/gully" at the front of the house is only there because I dug it out to investigate.
Before that, there appears to be no deliberate system to manage the rainfall that gathers on my driveway and at the front of my house.

In the attached picture it appears that I could attach some sort of drainage system (French drain/ACO) to the downpipe system because the ground falls away to that corner.

So, my main question, I suppose, is whether its worth the expense/bother/risk of carrying out work that previous builders/architects/surveyors seem to have decided unnecessary, or whether it's best just to leave it all to nature as seems to have been the case up until now.

 

[JohnD]

Before that, there appears to be no deliberate system to manage the rainfall that gathers on my driveway and at the front of my house.

In the attached picture it appears that I could attach some sort of drainage system (French drain/ACO) to the downpipe system because the ground falls away to that corner.

So, my main question, I suppose, is whether its worth the expense/bother/risk of carrying out work that previous builders/architects/surveyors seem to have decided unnecessary, or whether it's best just to leave it all to nature as seems to have been the case up until now.

It looks to me like the builder put in a fake hoping that no-one would notice until they were gone.

If there is no drainage system for the rainwater, adding one would be a very sensible move. Take the water away from the house as it may undermine paving or cause damp especially if the house is old.

If your soil is heavy clay the job will be more arduous than if the subsoil is reasonably porous.